Apparatus for simultaneously polishing both faces of a travelling strip of glass



H. BAILLIE G. APPARATUS FOR SIMULTANEOUSLY POLISHING BOTH FACES OF A TRAVELLING STRIP OF GLASS Flled Apnl 9 1946 April 29, 1947.

Inventor Attorney 3 Patented Apr. 29, 1947 ISHING BOTH FACES OF A TRAVELLING STRIP or GLASS Granville Hugh Baillie, London, England, assignor to Pilkington Brothers Limited, Liverpool, England, a British company Application April 9, 1946, Serial No. 660,714 In Great Britain September 13, 1944 2 Claims.

. 1 This invention relates to apparatus for simultaneously polishing both faces of a travelling strip of glass. V

Such form of apparatus commonly comprises polishing tools adapted to operate on the underface of the glass strip, whilst at the same time they serve to support the strip, each such tool including a plurality of polishing pads each adapted to turn on a substantially vertical axis, the tool being mounted on a frame which is adapted to rotate so as to bring each pad to an edge of the glass.

The tool may either be supported on a single frame with central driven shaft or may be supported on a plurality of sub-frames in turn supported on a main frame with central driven shaft, each sub-frame (if used) being free to rotate on its support on the main frame. Each tool is provided with means of vertical adjustment, whereby the strip of glass supported by the plurality of tools can be kept free of bends in passing through the apparatus.

Polishing is effected by the rubbing of the pads over the glass, while rouge and water is supplied either to the pads or to the glass. After a certain time of operation, rouge becomes caked on the pads to form a hard layer, in which foreign matter such as glass splinters may be embedded, and the polishing action is then impaired. The pads then have to be cleaned by removing the hard layer and, to effect this, access must be obtained to the operative surface of the pads. Further, the pad coverings gradually wear and may become damaged and then the coverings must be removed and replaced.

If a polishing tool operating on the under surface of a strip of glass be lowered so as to give access to the surfaces of the pads, there is risk of the travelling glass, which is then left unsupported over the tool, breaking. Also, if one or some of the pads have their covering replaced, the pads with new coverings are not accurately in the same plane as the remaining pads with partially worn coverings. This has the result of imposing bending stresses on the glass which may be sufficient to break the glass.

A main object of the present invention is to provide in apparatus for simultaneously polishing both faces of a travelling strip of glass, means whereby a pad operating on the underface of the glass can be rapidly moved away so that the pad can either be replaced or its surface scraped or cleaned, and its surface adjusted into the plane in which the other pads mutually support the glass.

In accordance with the present invention apparatus for polishing the under surface of a horizontal travelling strip of glass as it comes from the lehr comprises polishing tools which support the strip during polishing, each tool comprising a frame adapted to turn on a vertical axis, and a plurality of polishing pads supported on said frame, each pad being mounted to turn on a vertical axis, characterised by a supporting member for each pad pivoted to the frame about a horizontal pivot distant from the axis of the pad by at least the radius of the pad, a locking device individual to each pad mounted onthe pad. supporting member, said locking device when in operative position rigidly holding .the respective pad in polishing position on the. pad supporting member, and in inoperative position releasing the respective pad from said pad. sup-- porting member, whereby the pad is freed to fall about its horizontalpivotaway from the glass and to give access to its operative surface, and means individual to each pad for adjustingfithe pad along its vertical axis in the pad supporting member. f f

In the accompanying drawings is shown by way of example one embodiment of the invention as applied to apparatus for polishing glass including co-axial polishing tools operating simultaneously on both surfaces of the glass.

In the drawingsr Figure 1 is a plan view of a lower polishing tool with three pads, partly broken away, and without the glass strip above it;

Figure 2 is a vertical section on the line AA' of Figure 1; and

Figure 3 is an elevation partly in section on the line A-B of Figure 1.

The driving shaft I of the polishing tool carries a frame 2, which supports three polishing pads 3 with felt coverings 4, operating on the under surface of a travelling strip of glass 5, which is driven slowly by driving rollers (not shown) in known manner between co-axial polishing tools, of which the lower tool only is shown.

Each pad is supported by a pin 6 which is free to rotate in a sleeve l, which is adapted to slide vertically in the cup-shaped end 8 of an arm 9 pivoted at In in a fork of the frame. The arm 9 has a depending lug l l which, when the pad is in operative position as in Figures 1 and 2, is held in this position by two screws 12 passing through the fork of the frame and engaging recesses 13 in the lug. On withdrawing the screws i2 from the recesses l3, the arm 9 with the pad, is free to turn about its pivot l0 into the posi- .tion shown in Figure 3, in which its operative surface 4 is exposed to permit the felt covering to be changed, or the surface cleaned by scraping.

It is to be noted-thatthe pivot lflaofithe mem- 9 is verticallyibelowtheextremeedge of the,pad and that, consequently, no part of the pad has an upward motion as the pad moves from the position of Figure 2 to that of Figure 3. The pivot I may be further from the cen'tre lineof the-pad 9 than the extreme edge of padfbut-not-closer to it;

The sleeve 1 in which the pad is carried is supported vertically in the cup-.-shaped .end 8 ofithe member 9 by means of the :screw M in fthe :bottom of the end 8. By turning the screw rHLTthe height of the pad is adjusted, and thereby the operative surface of the pad may be brought into the plane coincident with the plane of the under surface of the strip of glass 5.

It is to be noted that, when a pad is moved "from its operative ;position ;to the :position of figure 8, ato give access :to its operative ;surface, :and is ireturned to its Qpetativeposition, i1JS10P- eerative isurface :reverts :.to Lthe original position it!) which it; had rheen adjusted by itheecrew l4.

'When it is .desired :to replace a felt the zpin :6 :can :be lowered to zfacilitateiaccess 1to=the ;pad as iinzanymase the 1pm would Lhave to he ,lOWGI'BditO accommodate ithe new :and :thicker .ielt.

:Bysmeans 10f .the construction :above described, ia'nyipadzmayibe withdrawn fr'omzthe glassrtoagive iaccess to :its surface, leaving ithe ;other padsi-in operative position supporting the :glass and, .furithar, each :pad its :adjustable ;in vertical meig-ht,

iandgthis:adjustmentrisinotidisturhedby the moveiment 10f :the mad giving access it!) .its :surface.

;In .the description .Just given the zpads are described {as ibeing mounted on vertical axes. the mass may, however, :bezslightlytilted 1from:the wertical and the term vertical 1used .hereiniis iintended ito include either a :truly "verticalzor isubstantially "vertical .axis.

Apparatus for polishing the undersurfaceiof ia=hoi izontal travelling :strip aof'glasszas :it comes 315 4 from the lehr comprising polishing tools which support the trip during polishing, each tool comprising a frame adapted to turn on a vertical axis, and a plurality of polishing pads supported on .said rframe, reach pad ,being slidingLV tmounted-andjournaleditofturn gnaw vertical axis, characterised by a supporting member for each ,pad pivoted to the frame about a horizontal pivot distant from the axis of the pad by at least the :radius of the mad, an independent locking device for each ,pad :mounted on the pad supporting meniber, each "locking device when in operative iposition rigidlyzholding its pad in polishing positionmn the lpadisuppcrting member, and in inoperative zposition releasing its pad from said pamsunp rting member, whereby the pad is freed 21101311 about its'horizontal pivot away from the glass and to give access to its operative surface, a'nd mdividual adjusting means for each pad for sliding the pad alon its vertical axis in the pad supporting member.

22. Apparatus :as recited in claim '1 wherein said individual adjusting means forte'achzpolishing =pad comprises a sleeve :mounted :for vertical movement in said-supporting member, :a :pin ide- -pending from the :p'ad and extending :into said sleeve, and a sleeve adjusting .memb er mounted insaid-supporting member below said sleeveand tunable to vary the vertical position "of said sleeve.

HUGH BAILLIE.

REFERENCES {CITED Ehe following references are :of rI'GCOl-d in the iflle 10f lthis :patent:

UN STATES PATENTS Number Name :Date 40 =1,536;847 :Heichert May 5, A925 1548; ESoderberg Augrld, 1925 1,872,694 Drttke Aug, 23, 31932 1,946,955 'Waldron Feb. 13, 1934 1;854g507 Drake Apr. '19, 1932 

